1. A marketing specialist is interested in investigating whether the number of coffeehouses in a city increases as rainfall increases. To investigate this, the researcher collects information on the number of inches of rainfall per year and the number of coffeehouses in a sample of 35 U.S. cities. She then uses this information to estimate the association between annual rainfall and the number of coffeehouses.

a. What is the dependent variable?
b. What is the independent variable?
c. What is the unit of analysis in this research?